This invention relates to an objective lens driving device used for an optical pickup for recording and/or reproducing data on and/or from optical disks or other data recording media and for operating a movable section to move in both the focusing and tracking directions, and it relates further to an optical pickup and an optical disk device using the aforesaid objective lens driving device.
An optical disk device is in existence for recording and/or reproducing data signals by using optical disks and other data recording media, and such an optical disk device is provided with an optical pickup which moves in the radius direction of the optical disk and irradiates an optical beam to the aforesaid optical disk.
The optical pickup is mounted with an objective lens driving device by which the objective lens retained on the movable section of the driving device is moved in the focusing direction, namely the direction of getting farther from or nearer to the signal recording face of the optical disk, for focusing adjustment, and also moved approximately in the radius direction of the optical disk for tracking adjustment. Through these movements of the objective lens, the spot of the optical beam irradiated on the optical disk through the objective lens is adjusted and thereby focused on the recording track of the disk
Such an objective lens driving device of the optical pickup has a frequency characteristic as shown by the curve G2 in FIG. 7, owing to the weight of the movable section and the elastic coefficient of the elastic supporting members. In the optical pickup, a resonance peak resulting from the elastic vibration of the movable section might deteriorate the characteristic of focusing servo in particular and disturb the performance of recording and/or reproducing data on or from the optical disk.